How Often Is 'Once in a Blue Moon'? Let Neil deGrasse Tyson Explain

From “lit” to “I can’t even,” lots of colloquialisms make no sense. But not all confusing phrases stem from Millennial mouths. Take, for example, “once in a blue moon”—an expression you’ve likely heard uttered by teachers, parents, newscasters, and even scientists. This term is often used to describe a rare phenomenon—but why?

Even StarTalk Radio host Neil deGrasse Tyson doesn’t know for sure. “I have no idea why a blue moon is called a blue moon,” he tells Mashable. “There is nothing blue about it at all.”

A blue moon is the second full moon to appear in a single calendar month. Astronomy dictates that two full moons can technically occur in one month, so long as the first moon rises early in the month and the second appears around the 30th or 31st. This type of phenomenon occurs every couple years or so. So taken literally, “Once in a blue moon” must mean "every few years"—even if the term itself is often used to describe something that’s even more rare.

Farther vs. Further: There’s an Easy Way to Remember the Difference, and When to Use Which

Even for native speakers, the English language is full of booby traps. That's why people are so hesitant to use whom instead of who, and why thinking about the differences between lay and lie is enough to give professional linguists a headache. One of the more common pitfalls is further vs. farther: Both words describe similar situations, and there's only one letter separating them. Though they're often used interchangeably, there is a difference between further and farther, and luckily for anyone who struggles with grammar, there's an easy trick to remember what it is.

Further and farther are both used in relation to progress, but the type of progress they describe differs. According to Quick and Dirty Tips, farther is reserved for physical distance, i.e. "the runner was farther down the track than his competitor," while further is used for figurative or metaphorical scenarios, such as "the senator was interrupted before she could go further in her speech."

The best way to remember this is to look at the first three letters of the words. Farther starts with far, a word that's associated with physical distance. This can remind you to use farther when describing things like car trips and walks, and save further for concepts like projects, movies, and dreams.

This distinction is clear enough, but things can get sticky when it's not totally obvious if a statement is dealing with physical or metaphorical distance. Take the sentence "the writer had gotten farther in her poem by the afternoon" as an example. If the progress being referred to is lines on a page, farther works just fine, but if the speaker is talking about the poem as a piece of art, further may be more more appropriate. In such instances, it's usually safest to default to further: Usage for farther is slightly stricter, and because further deals with situations that are already hard to define, you can get away with using it in more contexts. And if you still get them mixed up, don't let it bother you too much. Merriam-Webster notes that great writers have been using farther and further interchangeably for centuries.

11 Untranslatable Words for Happiness From Around the World

You know that feeling you get when you listen to your favorite song? Or the feeling you get when somebody cancels a meeting? You’d probably categorize both as happiness, but they’re not exactly the same emotion. And, while there are plenty of English synonyms for happiness—such as joy, pleasure, cheer, glee, contentment—none of them really capture either feeling with much precision.

In his new book, Happiness—Found in Translation, psychologist Tim Lomas creates a road map for identifying various types of happiness, filled with words from other languages that don’t necessarily have English equivalents. In addition to expanding your mental lexicon with beautiful vocabulary, Lomas argues that learning words to describe different feelings can actually magnify the feelings themselves. “Generally, the more awareness and understanding we have of our emotional lives, the greater our well-being,” he writes.

1. Shinrin-yoku (Japanese)

Annika Huett

“Forest-bathing.”

Going for a walk in the woods can sometimes clear your mind just as well as a good meditation session. There’s no English term to capture the restorative effect of immersing yourself in nature, but the Japanese call it shinrin-yoku.

2. Charmolypi (Greek)

“Sweet, joy-making sorrow.”

The best word we have to describe how you feel while celebrating the life of a loved one who recently died or waving goodbye to your toddler on their first day of school is probably bittersweet, but that doesn’t convey the depth of that peculiar happy-sad emotion quite like charmolypi does.

3. Fjaka (Croatian)

Annika Huett

“The sweetness of doing nothing.”

In a society that champions the ability to multitask above all else, not trying to check the next item off your to-do list can seem overindulgent or even counterproductive. But if you do manage to surrender your whole mind and body to not doing anything at all, it can feel almost euphoric. Croatians call this all-encompassing relaxation fjaka.

4. Pretoogjes (Dutch)

“Fun eyes.”

Have you ever met someone whose expression made you feel like you were in on a joke, without even knowing what the joke was? You might say they had a twinkle in their eye, which the Dutch call pretoogjes, or “fun eyes.”

5. Sólarfrí (Icelandic)

Annika Huett

“Sun holiday.”

In Iceland, employees are sometimes granted an unexpected day off to enjoy a warm, sunny day. Though sun holidays might be uncommon in the U.S., we’re well-acquainted with the nameless joy of unexpected freedom—many people experience it when their social plans get canceled.

6. Tarab (Arabic)

Annika Huett

“Musically induced ecstasy or enchantment.”

Though the specific songs, emotional reactions, and reasons behind those reactions may vary from person to person, being moved by music is a universal experience—even babies sometimes cry when they hear certain songs. In Arabic, this sense of losing yourself in the music is called tarab.

7. Sprezzatura (Italian)

“Nonchalant effortlessness.”

Often, as in the case of a ballerina’s grand jeté or Johnny Depp’s unruly lock of hair in 1990’s Cry-Baby, seemingly effortless grace is only achieved by years of practice (or gobs of hair gel). The ability to make something look so beautifully careless through careful study is known as sprezzatura in Italy.

8. Mamihlapinatapai (Yagán)

Annika Huett

“A look between people that expresses unspoken but mutual desire.”

A glance exchanged between two people who share a desire but are each hoping the other will make the first move is so full of nuance and complexity that we unsurprisingly haven’t come up with an English word to describe it. The Yagán people of Tierra del Fuego in Argentina and Chile did not have a similar issue—they named it mamihlapinatapai.

9. Etterpåklokskap (Norwegian)

“After wisdom.”

Mistakes, however dumb they may make us feel in the moment, are one of the best ways to learn and grow. Etterpåklokskap perfectly describes the grounded, enlightened feeling you get when you know exactly how to handle a situation because you’ve seen it (and screwed it up) before.

10. Engelengeduld (Dutch)

Annika Huett

“Angelic patience.”

The saint-like grace with which mothers react to just about everything that their kids do, from spitting up on their new blouses to throwing tornado-level temper tantrums in supermarkets, definitely deserves a special term. The Dutch call it engelengeduld.

11. Orka (Swedish)

Annika Huett

“Requisite energy for a task.”

Completing a task isn’t always just about having enough physical energy for it—you also have to care enough to actually expend that energy. You might have orka to throw a surprise birthday party for your best friend, but you might not have orka to study for a quiz that probably won’t affect your final grade.

Reprinted with permission from TarcherPerigee. Get a copy of Happiness—Lost in Translation for $13 from Amazon.

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